You can download the core 21 v 0.0.20 preview test core  [UPDATED 27 MAR 2017 15:15 EST]:

    md5 hashes:

    • MD5 (FahCore_21) = 5f2faffa3f632f1b6e8181de5d4454a4
    • MD5 (FahCore_21_32_amd.exe) = 4a4d1323c6e3520f9f4ed702e536fd5a
    • MD5 (FahCore_21_32_nvidia.exe) = 36b22ab4d4a4a68157780125e59eb86d
    • MD5 (FahCore_21_64_amd.exe) = 1520880876a17ffddb879b19216ad61a
    • MD5 (FahCore_21_64_nvidia.exe) = 325a91281e0cfdafa24a757195239143

    (If something goes wrong, just delete that file and the current release version of the core will be retrieved from the FAH servers.)

    Please configure your config.xml to include use client-type of internal and project-key between 11501-11514, e.g.

    <client-type v='internal'/>

    <project-key v='11501'/>

    Do not use any other project keys besides 11501-11514.

    When done, just delete the copies of FahCore_21 you overwrote and the client will re-download the current release version of the core. Please delete this core version before switching back to other non-test WUs!

    NOTE: These WUs are very short (under 5 min/WU) and are worth zero points to discourage others from trying to use them.


    Make the core executable with chmod a+x FahCore_21 if it isn't already.

    Before you start, make sure to stop your client. You will want to finish or terminate any WUs you are working on. Please remove (or rename) your work/ directory before proceeding.

    Replace your existing copies of FahCore_21 with this binary. For example, if you have an existing copy of FahCore_21 at


    replace it with this version.


    The paths will look something like



    All platforms